1. Field of the Invention
The present invention is related to a method of preventing particle generation in a semiconductor manufacturing process.
2. Description of the Related Art
When the semiconductor design rule is shrank to smaller than 0.15 um, the prevention and control of particle during semiconductor manufacturing is much more important. In the larger size design rule, for example, 0.25 um design rule, the particles with sizes of about 0.2 um do not cause a semiconductor circuit open or short. When the design rule, however, is down to 0.15 um, particles with the same size as above can cause a circuit to fail.
In the present semiconductor manufacturing process of 0.15 um technology, the contact/via hole size is about 0.2 um. To form a preferred contact/via hole profile, an dielectric anti-reflection coating layer formed under a photoresist layer is used as an anti-reflection layer to absorb the incident light to achieve an preferred photo pattern profile and to improve the subsequent contact/via hole etching profile. Generally, the dielectric anti-reflection coating layer is made from a silicon nitride or a silicon oxynitride layer. After the photoresist layer is removed by a dry etching step and a wet etching step, the anti-reflection coating layer is exposed on the substrate.
In the traditional semiconductor manufacturing process, after a photoresist layer is removed and before a barrier metal layer is deposited, an Ar sputtering clean step is provided to clean polymer or by-product generated during the contact/via hole etching step in the contact/via holes. When carrying out the Ar sputtering clean step, Ar ions bombard the dielectric anti-reflection coating layer besides removing the polymer or by-product in the contact/via holes such that the anti-reflection coating layer particles generated by the Ar sputtering clean deposit on the inside wall of the Ar sputtering clean chamber. Unfortunately, because the Ar sputtering clean chamber is made from silicon dioxide or quartz in general and the adhesion between silicon dioxide and silicon nitride or the adhesion between silicon dioxide and silicon oxynitride is poor, the dielectric anti-reflection coating layer particles deposited on the inside wall of the Ar sputtering clean chamber will detach easily. This phenomenon is a cause for the particle generation during the Ar sputtering clean step of the semiconductor manufacturing process.
The object of the present invention is to prevent the aforementioned phenomenon in a semiconductor manufacturing process.
One object of the present invention is to provide a method for preventing a particle generation when substrate is Ar sputtering clean.
In a preferred embodiment, a method for preventing particle generation when substrate is subjected to Ar sputtering clean is provided by the steps of first providing a dielectric layer on a substrate, then forming an anti-reflection layer on the dielectric layer, then forming a plurality of contact/via holes in the dielectric layer and the anti-reflection layer, then coating a sacrificial layer into the plurality of contact/via holes and on the anti-reflection layer, then removing the sacrificial layer and the anti-reflection layer on top of the dielectric layer, then removing the sacrificial layer in the contact/via holes, and finally performing an Ar sputtering clean.